int value = 1000;void setup() {  Serial.begin(9600);  Serial.println("Hello World!");  //just to have fun  pinMode(LED_BUILTIN, OUTPUT);}void loop() {  digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)  delay(value);                       // wait for a second  digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW  delay(value);                       // wait for a second  if (Serial.available()) {        int inByte = Serial.read();        if (inByte == 119){          value = value / 2;        }        if (inByte == 115){          value = value * 2;        }            }  value = constrain(value, 100, 6000);}